<!doctype html>

<html>

<head>
    <meta charset="utf-8">
    <title>11</title>
    <link rel="stylesheet" href="chosen.css">
</head>

<body>
    <select name="dept" data-placeholder="选择部门" style="width:210px;" id="dept" class="dept_select">
        <option value="-1"></option>
        <option value="部门1">部门1</option>
        <option value="部门2">部门2</option>
        <option value="部门3">部门3</option>
        <option value="a1">a1</option>
        <option value="b5">a5</option>
        <option value="c1">c1</option>
        <option value="d2">d2</option>
        <option value="e3">e3</option>
        <option value="f4">f4</option>
        <option value="g5">g5</option>
        <option value="h1">h1</option>
        <option value="i2">i2</option>
        <option value="g3">g3</option>
        <option value="k4">k4</option>
        <option value="l5">l5</option>
        <option value="m1">m1</option>
        <option value="n2">n2</option>
        <option value="o3">o3</option>
        <option value="p4">p4</option>
        <option value="q5">q5</option>
    </select>
    <script src="jquery-1.7.1.js"></script>
    <script src="chosen.jquery.js"></script>
    <script>
        $(function () {
            $('.dept_select').chosen();
        });
    </script>
</body>

</html>